The field of the invention is generally related to the fabrication of reed switches. More particularly, the invention relates to a machine and methods for semi-automatically assembling and sealing in correct alignment inside a glass envelope the plural contact pairs of a multi-element reed capsule.
In multi-element reed switches, plural pairs of magnetizable switch contact members are positioned in overlapping spaced relationship within a non-magnetizable envelope which most frequently is glass. The switch contacts are opened or closed through the selective application of a controlled magnetic field. Switches of this general type are well known and are used by the hundreds of thousands in telephone and other switching networks. Because of the large quantities needed, it is desirable that the final assembly of the switch contacts inside the envelope be made rapidly and that minimum variations in contact characteristics be maintained. One manner of achieving these goals is through machine assembly which is both faster than manual assembly and also more repeatable than manual operations. However, maintaining the precise alignments required all through the assembly and sealing process has proven difficult to achieve in a fast consistent manner. Some manual adjustment of alignment after assembly has been required or, a generally unsatisfactory rejection rate encountered.
Means are known in the prior art for facilitating the automatic manufacture of reed switches including in at least a conceptual sense a number of the basic steps and methods of this invention, but the prior art is lacking in a number of the refinements found necessary if automatic high-speed assembly with high quality dimensionally accurate assemblies are to be achieved. Thus the patents of Pityo, U.S. Pat. No. 3,537,276 and Reck, U.S. Pat. No. 3,203,081 are both directed to automatic assembly of reed switches but not, multi-element reed switches as with the invention.